rabbit,
which there can be little doubt would thus have been ranked as a distinct
species, has certainly originated since the year 1420. Finally, from the
three cases of the rabbits which have run wild in Porto Santo, Jamaica, and
the Falkland Islands, we see that these animals do not, under new
conditions of life, revert to or retain their aboriginal character, as is
so generally asserted to be the case by most authors.

_Osteological Characters._

When we remember, on the one hand, how frequently it is stated that
important parts of the structure never vary; and, on the other hand, on
what small differences in the skeleton, fossil species have often been
founded, the variability of the skull and of some other bones in the
domesticated rabbit well deserves attention. It must not be supposed that
the more important differences immediately to be described strictly
characterise any one breed; all that can be said is, that they are
generally present in certain breeds. We should bear in mind that selection
has not been applied to fix any character in the skeleton, and that the
animals have not had to support themselves under {116} uniform habits of
life. We cannot account for most of the differences in the skeleton; but we
shall see that the increased size of the body, due to careful nurture and
continued selection, has affected the head in a particular manner. Even the
elongation and lopping of the ears have influenced in a small degree the
form of the whole skull. The want of exercise has apparently modified the
proportional length of the limbs in comparison with the body.

[Illustration: Fig. 6.--Skull of Wild Rabbit, of natural size.]

[Illustration: Fig. 7.--Skull of large Lop-eared Rabbit, of natural
size.]

As a standard of comparison, I prepared skeletons of two wild rabbits
from Kent, one from the Shetland Islands, and one from Antrim in
Ireland. As all the bones in these four specimens from such distant
localities closely resembled each other, presenting scarcely any
appreciable difference, it may be concluded that the bones of the wild
rabbit are generally uniform in character.

_Skull._--I have carefully examined skulls of ten large lop-eared fancy
rabbits, and of five common domestic rabbits, which latter differ from
the lop-eared only in not having such large bodies or ears, yet both
larger than in the wild rabbit. First for the ten lop-eared rabbits: in